Packard Model 1A-1551

In early 1921, the Navy contracted with the Packard Motor Car Company, to develop the new Model 1A-1551 engine for its proposed ZR-1 airship, later named Shenandoah. The engine carried with it an instrument and control panel for the operator. A hand crank, with automatic engagement and disengagement and geared 10 to 1, was provided for starting. Due to the necessity of directing the exhaust away from the ship for side-by-side installations, the engines were designed so that they could be easily changed to run in either direction. Installed in 'cars' attached to the airship, five Model 1A-1551 engines powered the Shenandoah, which made its first flight in October 1923. Mechanics controlled and serviced the engines in flight from these cars. In October 1924, the Shenandoah became the first airship to make a U.S. transcontinental trip. But, in September 1925, the Shenandoah broke up in a severe thunderstorm near Caldwell, Ohio, and crashed. Artist Packard Motor Car Company. (Photo by Heritage Art/Heritage Images via Getty Images)